When constraining, right click an object to toggle its workplanes/axes. 

Watch the tutorial video here: www.youtube.com/watch?v=FE58cbDga7Q

The installer that ran when you downloaded this app/plug-in from Autodesk App Store will start installing the app/plug-in. OR, simply double-click the downloaded installer to install the app/plugin.

You can unload the plugin without uninstalling it by unchecking the "Loaded/Unloaded" checkbox associated with the plugin in the Inventor Add-In Manager. You may have to restart Inventor to completely unload the application.

To uninstall this plug-in, exit the Autodesk product if you are currently running it, simply rerun the installer, and select the "Uninstall" button. OR, you can uninstall it from 'Control Panel/Programs and Features' (Windows 7/8.1/10), just as you would uninstall any other application from your system.